Watts RE, Odedra A, Marquart L, et al. - As malaria resistance to artemisinin combination therapies is threatening malaria control, researchers developed and tested a human model of artemisinin-resistant (ART-R) Plasmodium falciparum to examine the efficacy of antimalarial drugs against ART-R malaria. Two malaria volunteer infection studies (VIS) were undertaken. In a pilot study, they infected 2 healthy participants with ART-R parasites. In a comparative study, infection with either ART-R (13 participants) or artemisinin-sensitive (ART-S; 9 participants) parasites was induced in participants. In both studies, a single dose of an artemisinin derivative (artesunate[AS]) was provided to the participants 8 or 9 days after infection. Participants in the pilot study (36 adverse events reported) as well as the comparative study (277 adverse events) well tolerated malaria; there were no serious adverse events in the studies. Headache, pyrexia, myalgia, nausea, and chills were the common adverse events. In the comparative study, clearance of parasites from the blood of participants took significantly longer time after AS administration among participants infected with ART-R parasites (6.5 hours) compared with participants infected with ART-S parasites (3.2 hours). As per researchers, this is the first human model of ART-R malaria. Results suggest that this model can be safely employed to appraise new drugs against ART-R P. falciparum.